The Deloitte Consumer Spending Index slipped in September in a second month of small declines. The index, which tracks consumer cash flow as an indicator of future consumer spending, isn’t necessarily projecting gloom, however.

"Although the Index moved down slightly last month, it remained in positive territory," said Daniel Bachman, Deloitte's senior economist for the United States. "These slight variations in economic fundamentals month-to-month during a period of economic recovery are not unusual. In the latest index, new home prices continued to rise, but the pace of growth is decelerating. Initial unemployment claims continued to fall, but real wages remain flat."

The index comprises four components: tax burden, initial unemployment claims, real wages and real home prices. Given the inputs, including an increase in tax burden, the index fell to 3.7 this month from 4.0 last month. Still, a number of factors that are currently impinging on the economy may be sufficiently short-lived for the current trend to turn around quickly.

"If the government shutdown is short-lived, retailers may not feel a noticeable impact, but if it persists, consumers may pause at the beginning of the holiday season," said Alison Paul, vice chairman, Deloitte LLP and Retail & Distribution sector leader. "With many retailers planning early promotions this year, shifts in consumer sentiment will likely test retailers' scenario planning techniques. They should run multiple scenarios now, so they can be nimble enough to make quick decisions about their promotions and pricing should demand suddenly tick up or down. Those efforts include analyzing store and online traffic patterns, mining social media for changes in consumer behavior and taking a closer audit of merchandise to determine what is sitting too long on the shelf and which items are effectively bringing customers through the door."